Ceramic materials are able to withstand much higher temperatures than metals. Accordingly, ceramics are well suited for high temperature applications. For instance, in the context of turbine engines, it would be advantageous to replace a metal combustor liner with a liner made of ceramic. A ceramic liner would be able to better tolerate the high thermal loads of combustion and, in turn, less air would need to be diverted from the combustion process for purposes of cooling the liner, allowing for potential increases in engine efficiency and reductions in the production of undesired combustion byproducts, such as NOx and CO.
However, these advantages are hampered by the difficulty of integrating a ceramic liner in a turbine engine combustor. Normally, each end of the liner is attached to one or more nearby combustor components, which are typically made of metal or other non-ceramic material. As the parts are heated, differences in the rate of thermal expansion of the ceramic liner and the components to which the liner is attached can subject the liner to unacceptably high stresses. Damage to the liner can result in extended outages and costly repair or replacement. As a result of such concerns, prior ceramic/non-ceramic attachment systems have relied on non-traditional and complex methods to protect the ceramic.
Thus, there is a need for a simplified system of attaching a ceramic liner to neighboring non-ceramic combustor components, while accommodating unequal rates of thermal expansion of such components.